This invention relates to a rotation sensor for detecting the number of revolutions of a gear-like magnetic rotation body, for example, and a manufacturing method therefor.
A rotation sensor for detecting the number of revolutions of a gear-like magnetic rotation body is proposed, for example, in Japanese Patent Laid-Open No. Hei 7-198736, in such sensor a magnetoelectric conversion device is used to detect a magnetic flux change caused by rotation of a magnetic rotation body, a terminal for outputting a signal of the magnetoelectric conversion device is insert-molded in a base made of resin, the magnetoelectric conversion device is electrically connected to the terminal, a part of the terminal is used as a surface mount electrode to mount electronic components, the surface mount electrode part is provided by bending the terminal to produce a layered, and a connector part is formed using the terminal end as terminal electrode.
For the conventional rotation sensor, the base made of resin and the connector part of an insert conductor are simultaneously formed by insert-molding. Thus, the resin pressure at molding causes the insert conductor to be deformed and adjacent insert conductors to be short-circuited. To prevent the insert conductor from being deformed, the insert conductor needs to be sandwiched and held between pins disposed in a metal mold at a large number of points at molding. Resultantly, the insert conductor is exposed to the holding parts. Thus, seal material needs to be applied to the insert conductor exposure parts to prevent moisture entering from the outside from causing a short circuit. As a result workability is poor.
Further, the surface mount electrode part formed by the insert conductor is layered. To provide a layered structure, two or more bending steps are required and workability is poor.
To provide a layered structure, the electrode area before bending requires twice that after bending at each surface mount electrode, thus the number of surface mount electronic components cannot be increased and freedom of layout is restricted.